In the Philippine jurisdiction, retirement is not merely a cessation of work but a legally defined transition governed by specific statutes, administrative regulations, and contractual agreements. Early retirement—retiring before the compulsory age of 65—requires adherence to distinct criteria depending on whether the individual is employed in the private sector or the public sector.

I. Private Sector Retirement (Republic Act No. 7641)

The primary legislation governing retirement in the private sector is Republic Act No. 7641, which amended Article 287 of the Labor Code. It establishes the "Retirement Pay Law."

1. Eligibility Requirements

In the absence of a retirement plan or agreement in the establishment, an employee may retire and receive terminal benefits upon reaching the following milestones:

Optional Retirement Age: At least sixty (60) years old.
Service Requirement: Must have served the establishment for at least five (5) years.

2. Retirement Pay Calculation

Under RA 7641, the minimum retirement pay is equivalent to at least one-half (1/2) month salary for every year of service, where a fraction of at least six (6) months is considered as one whole year.

The "one-half month salary" is defined by law to include:

Fifteen (15) days salary based on the latest salary rate.
Cash equivalent of five (5) days of service incentive leave.
One-twelfth (1/12) of the 13th-month pay.
Totaling approximately 22.5 days per year of service.

3. Collective Bargaining Agreements (CBA)

The law serves as a floor, not a ceiling. If a company has a retirement plan or a CBA that provides for early retirement at an earlier age (e.g., 50 years old or after 20 years of service), those terms prevail, provided the benefits are not less than those mandated by RA 7641.

II. Public Sector Retirement (GSIS Laws)

Government employees are governed by the Government Service Insurance System (GSIS) under Republic Act No. 8291.

1. Eligibility for Early Retirement

A government employee may opt for early retirement if they meet the following "Three-Condition Rule":

Service Requirement: Must have rendered at least fifteen (15) years of service.
Age Requirement: Must be at least sixty (60) years old at the time of retirement.
Status: Must not be receiving a monthly pension for permanent total disability.

2. Retirement Modes

RA 8291 (GSIS Act of 1997): Provides for a 5-year lump sum (60 months of pension) followed by a monthly pension after five years, or a cash gift plus immediate monthly pension.
RA 1616 (Take-All Mode): For those who entered service before June 1, 1977. This allows for retirement regardless of age, provided the employee has served at least 20 years. Benefits include a refund of GSIS premiums and a gratuity payable by the employer (agency).

III. Social Security System (SSS) Retirement

For private-sector workers, the SSS provides the pension component, which is distinct from the retirement pay given by the employer.

1. Optional Retirement Age

An SSS member may claim retirement benefits starting at age 60, provided they are no longer employed (or are self-employed/voluntary members).

2. Contribution Requirement

To qualify for a monthly pension, the member must have paid at least 120 monthly contributions prior to the semester of retirement. If the member has not reached 120 contributions, they are entitled to a lump sum amount equal to the total contributions paid, including interest.

IV. Special Categories: Underground Mine Workers

Under Republic Act No. 10757, the retirement age for underground mine workers was lowered in recognition of the hazardous nature of their work:

Optional Retirement: Fifty (50) years old.
Compulsory Retirement: Sixty (60) years old.
The employee must have served at least five (5) years as an underground miner.

V. Tax Implications

Under the National Internal Revenue Code (NIRC), specifically Section 32(B)(6)(a), retirement benefits received by officials and employees of private firms are exempt from income tax if:

The retirement plan is reasonable and approved by the Bureau of Internal Revenue (BIR).
The retiring official or employee has been in the service of the same employer for at least ten (10) years.
The retiring employee is at least fifty (50) years old at the time of retirement.
The tax exemption is availed of by the employee only once.

VI. Summary of Compulsory vs. Optional Retirement

Sector	Optional Age (Early)	Compulsory Age	Key Service Requirement
Private (RA 7641)	60 Years Old	65 Years Old	5 Years
Public (GSIS)	60 Years Old	65 Years Old	15 Years
SSS Pension	60 Years Old	65 Years Old	120 Months Contributions
Miners	50 Years Old	60 Years Old	5 Years

Failure of an employer to pay the mandated retirement benefits constitutes a labor law violation, falling under the jurisdiction of the National Labor Relations Commission (NLRC).